Limiting a textarea to a fixed number of chinese characters

Question

I had been given a requirement from client saying limit the textarea – 200 characters in English, it is approximate 66 Chinese characters for UTF8.

I wonder how do I check them whether it is chinese character or english character and calculating them in the sense of maximum length ?

Is it your client's requirement to impose a different limit on chinese characters? — Pekka, Aug 10 '11 at 07:44
Pekka: my company client said so. Subdigger: what is the different between UTF8 and UTF16? Anyway I did make my page to UTF8 and chinese readable tho @@' — Eric T, Aug 10 '11 at 07:48
please check if this can help you: http://stackoverflow.com/questions/4877326/how-can-i-tell-if-a-string-contains-multibyte-characters-in-javascript — Dreaded semicolon, Aug 10 '11 at 08:33

score 0 · Accepted Answer · answered Aug 11 '11 at 02:07

Alright so I found a way (UTF-8 based) and somehow useful for me. But when I thought of client side, it was somehow still "yucks" ever since they are still able to edit it when inspect the dom element.....

Please advice me. Thanks

Code: My textarea and count box:

<textarea class="message" name="quiz_answer" cols="30" rows="4"></textarea><br />

<span class="countdown"></span>

Jquery document ready:

updateCountdown();

$('.message').attr('maxLength','25');

$('.message').keyup(updateCountdown);

updateCountdown function():

var previous = '';
var current = '';


//Count textarea words

function updateCountdown() {



var countMe = $(".message").val();

if(previous==''){
            previous = countMe;
            current = countMe;
}else{
            current = countMe;
}


    var escapedStr = encodeURI(countMe);

    if (escapedStr.indexOf("%") != -1) {

        var count = escapedStr.split("%").length - 1;

        if (count == 0) count++  //perverse case; can't happen with real UTF-8

        var tmp = escapedStr.length - (count * 3);

        count = count + tmp;

    } else {

        count = escapedStr.length;

    }



// 200 is the max message length

var remaining = 200 - count;



$('.countdown').text(remaining + ' characters remaining.');



if(remaining < 0){
            $(".message").val(previous);

}else{
           previous = current;

}

}

Limiting a textarea to a fixed number of chinese characters

1 Answers1